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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Sensor Centerpoint out of x axis

R

Rainer Fritz

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Hi !

So we tried it with a Angenieux 15-40 zoom. Also mounted the zoom upside down to test it if its really the chip. We tested it with both cams we have and its on the second exact the same. The Mysterium Sensor is in the X axis out of the middle. Point your mouse on the center of the siemens star and look to the video and you can see it by yourself:

http://redcamservice.eu/vids/centerpoint.mov

regards
rainer
 
Also tried different zooms on both cams. Also up side down. It is exact the same. Seems to be a factory fault.
 
Huh? This cannot be the sensor. I mean, it's the lens that projects an image onto the sensor and if the sensor was offset, it would be offset exactly the same, independent of the focal length of the lens.
 
think about what happens if the center of the mount is not the same of the sensor ?
 
The Sensor and the lens need to be aligned with each other.

Most chip blocks move on turn screws in order to do this alignment.

I don't have my camera yet so I can't duplicate this.

Does the lens mount allow you to shift the lens from side by side with some type of shim?

Dave
 
Hey Rainer... if your sure you were accurate in your tests, you can send your camera back to RED and we can make sure the sensor is aligned for you, its not something you can do in the field.
 
rainer said:
think about what happens if the center of the mount is not the same of the sensor ?
Click to expand...

Yeah, you're right. I see now. The actual centerpoint is somewhere NE of the Siemens star center. (And as I said it stays at the same place :wink:)

I think that this could be fixed in software by reading a different part of the sensor. No need to physically move it. Although the offset is quite large in this case... :unsure:

I cannot test it here with my RED because I don't have a zoom at hand - still waiting for my metric RED 18-50 mm... :angry02:
 
Is it possible that both zooms could have been calibrated on the same machine?

What I'm getting at is there is a super small and unlikely possibility they could have both been set up improperly.
 
Rainer,

The best test is to use the center marks in the viewfinder/LCD.

Pick a point to center the mark on, then zoom in... If it's off you will never hit the point with the mark over it.
If it's properly aligned the VF /LCD mark will always hit your reference point.

Dave
 
I have checked several here and they are all dead on.

But it is certainly possible that a sensor might have been slightly misaligned during assembly and if that is the case we will fix it.

Jim
 
Ok Guys, we will give a second chance :)

The zooms are for sure ok.... tried it with the 15-40 a 17-80 and a optimo could be that I misaligned the chart... we will do another one.

regards
rainer
 
Have the same with RED222, but because I'm busy, I can not send back the camera yet. I know it since the first lens tests I made, out of center, yes. But ok, hope I can wait to send it back, until 2222 is coming. And by the way: I wrote to RED support about that: never an answer.
 
rainer said:
Ok Guys, we will give a second chance :)

The zooms are for sure ok.... tried it with the 15-40 a 17-80 and a optimo could be that I misaligned the chart... we will do another one.

regards
rainer
Click to expand...

Rainer, let us know if the result is the same. Thanks
 
Hmmm, can't find this one, but I have an other from which I never get an answer: [RED #24247] :innocent: Or did it landed in SPAM? This problem I had two days ago again: I started record, some seconds later I got a looped frame, had to restart the camera again. All was gone, several takes later the same issue. Nothing special about settings, nothing special about storage.
 
How Much tracking error do the lenses have? Any Tracking error in the lens will be compounded by any error in the camera. Also, at what distance are you doing the test? Best distance would be 10ft, and measure the error.

Good idea to rotate the lens 180 deg, any zoom tracking error, will show tracking in the opposite direction.
 
So we did some testing again, and our first cam is on the way back to center it. We will shoot a big feature with the Optimo as a standard zoom lens and its impossible with this failure.
Red stated that we will have it back latly after 10 days as we sent it. Said they will need two days to fix the problem.
Our distance to the chart was about 10ft. I will not post new footage from the test, the results were the same.
Tested three different zooms and its always exact the same also when we turn them upside down. So there is for sure not the problem on the lenses which costs nearly three times than the body of the red one.... :)
As Daniel stated he saw the problem also as we stood in contact with a big rental house in munich/germany which have all cams the same problem....

regards
rainer
 
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